PURPOSE: To sense a steering force and its direction without being affected by inertial force by detecting the bending strain of a bending beam one end of which is fixed to a hub side while the other end to a spoke cover, by means of a strain gauge.
CONSTITUTION: When steering, a ring cover 17 is relatively moved with respect to a steering wheel ring 14. Accompanying this, a spoke cover 16 is relatively moved with respect to spokes 12, 13. Thereby, a bending beam 15 one end of which is fixed to a hub 11 side while the other end being fixed to the spoke cover 16, is also bent in the relatively moving direction, and this bending strain is detected by a strain gauge 18, to sense steering force. This sensed steering force is converted into an electric signal, to control the variable throttle of the hydraulic circuit of a power steering. By this construction, steering force can be accurately detected without being substantially delayed, while without being affected by the inertial force of the steering wheel 14, securely preventing delay in steering of the power steering.